/*
 * Copyright 2010 Askar Kalykov, oxygene.core@gmail.com
 *
 *    Licensed under the Apache License, Version 2.0 (the "License");
 *    you may not use this file except in compliance with the License.
 *    You may obtain a copy of the License at
 *
 *        http://www.apache.org/licenses/LICENSE-2.0
 *
 *    Unless required by applicable law or agreed to in writing, software
 *    distributed under the License is distributed on an "AS IS" BASIS,
 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *    See the License for the specific language governing permissions and
 *    limitations under the License.
 */

package com.oxygenecore.processor.expression;

import com.oxygenecore.processor.LeafExpression;
import com.oxygenecore.processor.ExecutionContext;

/**
 * @author Askar Kalykov
 *         Date: 11.09.2010
 *         Time: 16:23:58
 */
public class Constant<T> implements LeafExpression<T> {
    private final T value;

    public Constant(T value) {
        this.value = value;
    }

    public T getValue(ExecutionContext executionContext) {
        return value;
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;

        Constant constant = (Constant) o;

        if (!value.equals(constant.value)) return false;

        return true;
    }

    @Override
    public int hashCode() {
        return value.hashCode();
    }

    //todo replace to memcache?
    public static <V> Constant<V> get(V value){
        return new Constant<V>(value);
    }
}
